Just because you have 4x sticks of RAM doesn't mean it's instantly quad-channel. Your MoBo says if the RAM runs in quad-channel or not. Also, any MoBo that has 4x RAM slots only has dual-channel as max. Quad-channel MoBos have 8x RAM slots.
As far as RGB goes, it may be the error of that specific RAM. Or the RGB input signal gets a bit delayed between RAM sticks, resulting in uneven lightshow. Also, for unified lightshow, buy one set of 4 RAM sticks, not two sets of 2 RAM sticks since with set of 4, RAM manufacturer has proven that all 4x RAM sticks are working together without issues, including RGB they may have on.